1. Field of the Invention
The present invention relates to an improved needle for directional and atraumatic placement of the needle into a vascular system or body tissue for the purpose of performing multiple invasive procedures.
2. State of the Art
Needles and needle systems are used extensively in a wide variety of procedures which are performed in various fields of medicine, such as cardiology, radiology, urology, interventional pain management, and internal medicine. The use of needles and needle systems in invasive procedures in various medical fields has become routine due, in part, to the ability of needles to pass through most tissues without causing significant destruction to the tissues.
Conventional hypodermic needles, such as those used with hypodermic syringes in the administration of intravenous fluids, are well known in the medical arts. Hypodermic needles such as these are usually used in conjunction with various types of disposable hypodermic syringes for administration of medications like antibiotics, narcotics, biologicals, and vitamins. Hypodermic needles are also utilized in a number of diagnostic and therapeutic procedures, such as aspiration, blood draws, and biopsies. As more fully described in conjunction with FIG. 1 below, hypodermic needles are typically made of metal, consist of a hub that locks to a tip of the hypodermic syringe by friction or through a locking mechanism (known as Luer-Lock(trademark)), and typically include a point (usually in the form of a beveled cutting edge) of varying diameter and length.
Another widely-used type of needle system includes a system that employs a catheter and guide member. Such needle systems generally include a small guide member (e.g., guide wire) which is used to guide a larger hollow catheter to a target area (e.g., a vessel, body cavity, tissue, or organ) within a human or animal body. In use, the guide member is directed to the proximity of the target area using a hollow cannula or needle. The cannula is inserted into the body and positioned with its distal end in contact with or adjacent to the target area within the body. The guide member is advanced through the cannula to the target area. The cannula is then removed and the catheter is advanced over the guide member and into or to the target area. The guide members of these intravascular catheterization systems typically consist of a rigid wire or rod and a flexible tip that enables the guide member to be directed around obstacles and through curved vessels without causing damage to tissues or body structures as the tip of the guide member is advanced into or to the target area of the body. The guide member is advanced to the desired location within the body through a cannula. The cannula is then removed and a catheter is advanced over the guide member to the target area within the body.
Intravascular catheterization systems, such as those described above, have proven useful and efficient for both therapeutic and diagnostic purposes. For example, intravascular catheterization therapies, such as angioplasty and atherectomy, have been developed and widely used to treat vascular diseases or other conditions that occlude or reduce the lumen size of portions of a patients vascular system. In particular, balloon angioplasty has proven to be a useful and commonly-used treatment for obstructive coronary diseases. Additionally, intravascular catheterization systems have been used to perform various diagnostic procedures, such as angiographies, blood flow measurements, and ultrasonic imaging. These intravascular diagnostic systems may be used in conjunction with the aforementioned therapeutic intravascular catheterization systems or may be used in conjunction with other invasive techniques, such as coronary surgery.
Due to the small size or position of the target area and the tortuous passages through the patient""s vasculature, positioning of a catheter or needle to such target areas can be a difficult and time consuming task requiring considerable skill on the part of the health-care provider. Although currently-available intravascular catheters that employ a separate guide member provide advantages relating to placement, these catheters obtain this advantage at the expense of size and stability. Accordingly, there is a need for needles and needle systems that possess very small profiles and that can be positioned in narrow, tortuous regions of a vasculature or in a target area having critical dimensions in the body of an animal or person.
The present invention relates to an improved needle for directional placement of the needle into or to a target area, such as a blood vessel or organ, for the purpose of performing an invasive procedure with a minimal amount of trauma to the target area. The needle comprises a connection hub, a needle shaft, and a flexible tip member connected to a distal end of the needle shaft to facilitate maneuvering the needle through tortuous passages within the body. The flexible tip member includes a blunt end that prevents or reduces trauma to tissues and vessels that are contacted with the distal portion of the needle during positioning of the needle.
The invention further comprises a flexible-tipped needle having a balloon sealingly attached to a distal end of the flexible tip member. The flexible-tipped balloon needle includes an inflatable balloon sealingly connected to the distal end of the flexible tip member. The inflatable balloon has an interior portion that is in fluid communication with a first bore located within the hub and a second bore located within the needle shaft. The flexible-tipped balloon is intended for use in a number of procedures requiring dilatation of target areas within the body, such as a ureter for the evacuation of stones or blood vessels for treating hardening or blockage of the vessels. Alternatively, or in addition to the balloon connected to the distal end of the flexible tip member, the flexible-tipped needle can include a balloon that surrounds and is scalingly connected to the needle shaft.
The invention also includes a flexible-tipped needle having an insulated needle shaft, an insulated flexible-tip member, a blunt conductive end and a conductive wire extending from the blunt conductive end to an apparatus for sending or receiving electromagnetic signals.